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interactionsVercel

Mobile Input Size

MUST

MUST: Mobile `<input>` font-size ≥16px or set: ```html <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, viewport-fit=cover"> ```

Input font size must be at least 16px on mobile to prevent zoom

Bad

Good

Why it matters

iOS Safari automatically zooms when focusing inputs with font-size below 16px, causing disorienting page shifts. Either set font-size to 16px or larger, or use the viewport meta tag to control zoom behavior.

References

Built by Gleb Stroganov, design engineer at Evil Martians.

The rules come from other people's skills and guidelines — Vercel, Rauno Freiberg, @Ibelick, impeccable, Emil Kowalski, Tailwind, RAMS — each one credited on the Sources page. The work here is extraction and wiring: every rule is pulled into one corpus, given a good and a bad example you can operate, a MUST/SHOULD/NEVER rule an agent can paste, and a link back to where it came from.